1. Research Framework
1.1 Background
Theurgencyofaddressingclimatechangeandpromotingsustainable developmentinarchitectureismorecrucialthanever.Asbuildingsconsumea substantialamountoftheworld'senergyandresources,theenvironmentalimpact oftheirconstructionandoperationcannotbeignored.Embodiedenergy,which accountsfortheenergyusedinmaterialsproduction,construction,and transportation,constitutesalargeportionofabuilding’stotalcarbonfootprint,itis criticaltounderstandtheneedofassessingsuchlong-termenvironmentalimpactof existingbuildings.Therebyprovingifthebuildingneedstobedestroyedor adaptivelyreused.“Withbuildingsaccountingforover20percentofourcarbon emissionsandmorethanathirdofelectricityconsumption,reducingabuilding’s carbonemissionscangoalongwayinenablingustomeetournet-zeroby2050 target”saidbysecondministerofSingaporefornationaldevelopmentIndranee Rajah,attheinternationalgreenbuildingconference2023.1Althoughsomeheritage structureshavebeenpreservedandrestoredinSingaporeovertime,thelossofthe originalbuildingscausedirreversibledamagetoboththebuiltenvironmentandthe carbonfootprintthathadalreadybeeninvestedintheirconstruction.
Theeconomicviabilityofadaptivereuseversusdemolitionoftenpresentsa challenge,asthecostsofrepairingheritagebuildingscanbehigh,butthelong-term beneitsintermsofsustainability,communityvalue,andculturalpreservation cannotbeoverlooked.Sustainabilitynotonlyfocusesonenvironmentalbeneitsbut alsomustconsiderthesocialvalueandculturalheritageofbuildings.Preserving
1 https://www.straitstimes.com/multimedia/graphics/2024/09/singapore-conservedproperties/index.html?shell
ensuringthelong-termsustainabilityofheritagebuildings,includingenergyuseand maintenance,withoutunderminingthehistoricalsigniicance.
Thefollowingseveralreal-timeglobalexampleshavebeenexaminedfor broaderunderstandingwhereenvironmentalsustainabilityvalueandheritage conservationbecameinterlinkedinpublicdebate,particularlyinthecontextof climatechangeandsustainableurbandevelopment.Inthesecases,oppositiontothe demolitionofheritagebuildingswaslargelydrivenbyenvironmentalconcerns, includingtheembodiedenergyandcarbonfootprintassociatedwiththeexisting structures.
EdiicioEspañainMadrid,2006
TheEdiicioEspañaisahistoricskyscraperinMadrid,originallybuiltin1953. Itisalandmarkinthecity,knownforitsdistinctivedesignandhistoricalimportance. However,intheearly2000s,thebuildingwassettobedemolishedfor redevelopmentpurposes.Therewassigniicantpublicoppositiontothedemolition ofthebuilding,frombothheritagegroupsandenvironmentalactivists.The protestorshighlightedhowthedemolitionofthebuildingwouldresultina signiicantlossofembodiedenergy,andnewconstructionwouldrequiretheuseof morematerials,energy,andresources,furthercontributingtocarbonemissions. Whilethebuildingwasrenovatedandadaptedformodernuseratherthan demolished,theprotestshelpedtoraiseawarenessabouttheneedforasustainable approachtourbanconservationandtheimportanceofadaptivereuseinpreserving bothheritageandenvironmentalvalue.
CanberraCivicCentreinCanada,2010s
TheCanberraCivicCentrewasa1960smodernistbuildinginOttawa,Canada, thatfacedpotentialdemolitionduetoitsagingconditionandcitydevelopment plans.Public,environmentalistsandheritageconservationistsprotestedtheplanned demolition,focusingonboththearchitecturalandenvironmentalimplications.They arguedthattheenergyrequiredtodemolishthebuildingandthecarbonfootprintof constructinganewonewouldfaroutweighthesustainabilitybeneitsofadaptive reuse.Theenvironmentalvalueofpreservingtheembodiedenergyintheoriginal structurebecameacentralpartoftheprotestargument.Theprotestsledtoashiftin localpolicytowardmoresustainableurbanplanningandheritagepreservation.
PalaisdesCongrèsinParis,2015
ThePalaisdesCongrèswasamodernistbuildinginParisdesignedby architectJeanProuvé,apioneerinmodularconstruction.Thebuildingwas consideredalandmarkofmodernarchitectureandanexampleofinnovative buildingtechniques.However,in2015,therewereplanstodemolishitandreplaceit withanewdevelopment.Agroupofenvironmentalists,heritageactivists,and architectscametogethertoprotestthedemolitionofthePalaisdesCongrès.While muchoftheprotestfocusedonitsarchitecturalandhistoricalsigniicance,the environmentalargumentwasalsocentral.Theprotestorsarguedthatadaptivereuse andretroitwouldbemoresustainable,reducingthecarbonemissionsassociated withnewconstruction.Theprotestreceivedsigniicantmediaattention,especially duetothebackingofwell-knownarchitectsandenvironmentaladvocates. Eventually,thebuildingwassavedfromdemolition,andthefocusshiftedtoadapting itformodernuse,whichwasseenasavictoryforbothculturalpreservationand environmentalsustainability.
WhileSingaporehasanumberofsustainabilitycertiicationschemesfor buildingslikeBCAGreenMark5,theseschemesareoftendesignedformodern buildings.Heritagepropertiesfaceuniquechallengesthatmakeitdificulttomeet thesamesustainabilitycriteriawithoutcompromisingtheirhistoricalvalue.In Singapore,thereisageneralfocusonenergyeficiencyformodernbuildings,but thereisnocomprehensivesustainabilityframeworkforheritagebuildingsthat combinesheritageconservationandenvironmentalsustainabilityinaclear, actionableway.Theexistingconservationguidelinesmaynotalwaysconsider sustainabilityasaprimaryfactorwhenproposingordesigningconservationorA&A work.However,currentGreenMarkcertiicationsystemsandpolicies,whilewellintentionedinpromotingsustainablebuildingpractices,failtofullyaddressthe uniquechallengesposedbyheritagebuildings.Therigidapplicationofmodern sustainabilitystandardsoftenconlictswiththepreservationofhistorical,cultural, andarchitecturalvalues.HeritagebuildingsinSingapore,whichareintegraltothe city’sidentity,oftenstruggletomeetGreenMarkrequirements,duetotheirage, design,andthelimitationsimposedbyconservationneeds.Toaddressthese challenges,thereisaclearneedforpolicyadaptationsthatstrikeabalancebetween sustainabilityandheritagepreservation.
Thecentralpremiseofthisdissertationistoexplorethedevelopmentand applicationofanintegrateddecision-makingtoolthatassistsurbanplanners, architects,andpolicymakersindeterminingthemostsustainableapproachfor heritagebuildings-whethertoconserveortooptforcompletedemolition.
5 Building and Construction Authority is the government agency responsible for regulating and promoting sustainable construction in Singapore, including setting policies related to building codes, energy e iciency standards, and sustainable construction practices.
ArchitectureNetwork(mAAN)’s ButterlyMethod,thestudyaimstocontributeto theacademicunderstandingofsustainablegreenmarkbuildingsinSingapore.
1.3 LiteratureReview
Thissectionprovidesacomprehensivereviewoftheexistingliterature, identifyingkeythemesandproceedtoinfertheresearchgapsandquestions.The selectionandsynthesisoftheliteraturewereguidedbythestudy’srelevancetothe researchtopic,chosenmethodologies,and,insomecases,thepublicationdateand countryoforigin.Thecriteriaforselectingrelevantliteraturewerethepresenceof atleasttwoofthefollowingaspects:historicbuildings,greenmark,embodied energyorembodiedcarbonassessment,LifeCycleAssessment(LCA)methodology.
Legislation, regulations and guidelines on embodied energy in heritage or historical buildings
Wiseetal.(2019)analysesfurtherchallengestocalculatethisembodiedcarbonand theneedforlegislationonembodiedenergyinheritagebuildings.Themainmessage ofthisarticleexplorestheutilizationofacomprehensivedecision-makingtoolto determinethemostoptimalcourseofactionforoldbuildings,weighingthemeritsof adaptivereuseandrepairagainsttheoptionofcompletedemolition.Althoughthis researchishelpfulforunderstandingthecriticalroleofmultidisciplinary approachesindecision-making,itwouldbemorevaluableifithadexploredthe underlyingcausesforthelackofauniiedframeworkorregulatorystandardsinthis context.
Mahmadetal.(2024)highlightsthelackofpoliciesaddressingcarbon considerationsandsuggestsintegratingembodiedcarbonassessmentinto conservationdecision-makingforsustainableheritagepreservation.Butitsreview lackdepthinquantitativeanalysisandconcretepolicyrecommendations.While acknowledgingtheneedforembodiedcarbonassessment,thestudyfallsshortin proposingactionableframeworks,makingitsimpactonreal-timeconservation limited.
Boththeseliteraturesarguethattheabsenceofstandardizedtoolsforcalculating embodiedcarboninheritagebuildinghascontributedsigniicantlytothelackof awarenessamongpolicymakers.Withoutareliableandwidelyaccepted methodology,decision-makersareunabletoassesstheenvironmentalimpact effectively,leadingtothenegligenceofembodiedcarbonconsiderationsinexisting conservationpoliciesandregulations.Thus,highlightstheurgentneedfor developingpracticalassessmentframeworkstobridgethisgap,ensuringthat informeddecisionscanbemadeonwhetheraheritagebuildingshouldbepreserved ordemolished.
Circular economy and incentives
PullenandBennetts(2011)provideacompellingargumentforcostsavingsin historicbuildingconservation,yettheiranalysisoversimpliiesthe inancial motivationsofpropertyowners.Whilea10–25%costreductionisinferredfromthe casestudyofhistoricvilla,theargumentbecomesweakasitunderestimatesfactors likemodernbuildingadvantages,housingdemandsetc,whichmaystilldriveowners towarddemolition.
InAl-Zrigat(2025),thecirculareconomyconceptisintegratedintotheproposed BIM-basedframeworkforminimizingembodiedenergyinheritagebuildings. Insteadofrelyingontraditionallinearconstructionmodels(extract,use,and dispose),theframeworkencouragestheselectionofeco-eficientmaterials,local sourcingtoreducetransportationimpacts,andthereuseofexistingbuilding componentswhereverpossible.Thiscircularapproachsupportscost-effective conservationwhilemaintainingthehistoricalandculturalintegrityofheritage buildings.
Inconclusion,boththesestudieseffectivelyintegratecirculareconomyprinciples intoheritagebuildingconservation,butitsapplicationremainsmostlytheoretical. Additionally,therelianceonBIMandLCAtools,thoughinnovative,assumesalevelof technologicalaccessibilitythatmaynotbepracticalinmanyheritageconservation projects,particularlyinregionswithlimiteddigitalviability.Amorecomprehensive discussiononpolicyincentives,stakeholderengagementetc,inthecontextof circulareconomyadoptionwouldstrengthenthestudy’simpact.
TheJackson(2005)paperreliedonmanualcalculationmodels—theconcept, inventory,andsurveymodels—toestimateenergyuseinbuildingmaterials.These models,thoughfoundational,werelimitedinprecisionduetooutdatedindustry dataandalackofreal-timeanalyticalcapabilities.Incontrast,the2025studybyAlZrigat(2025),integratesBuildingInformationModelling(BIM)withLifeCycle Assessment(LCA)tominimizeembodiedenergyinheritagebuildings.This approachallowsforautomated,real-timedataprocessing,reducinghumanerror andenhancingaccuracy.Despitetheseadvancements,gapsremain.WhileBIM enablesdetailedmodelling,itsintegrationwithsustainabilityassessmenttoolsis
sustainabilityandembodiedenergyassessments,theselectedstudieswere organizedinreversechronologicalorder.
Year Reference
2025 Al-Zrigat, Z.M.(2025),"BIM frameworkto minimizeembodied energyinheritage buildings:old downtownAmman case studies", Facilities, Vol.43No.1/2,pp. 149171.
Methodology
Transformand Load(ETL) technologies, AutodeskRevit
2024 MSMahmadetal (2024)IOPConf.Ser.: EarthEnviron.Sci. 1347012024Faculty ofCivilEngineering &BuiltEnvironment, UniversityTun HusseinOnn Malaysia,BatuPahat, 81300,Johor, MALAYSIA
Qualitative Environmental Maintenance Impact(EMI)
2023 Fernandes,J.;Ferrão, P.ANewFramework forCircular Refurbishmentof Buildingsto Operationalize CircularEconomy Policies.
Environments2023, 10,51.
CaseStudy Applicationinthe Portuguesecontext.
Findings
Recommendsthe futureresearchto incorporatecost analysis,circular economystrategies, incentivesintoBIM frameworksto provide quantitative evidenceto determinevarious optionstoconserve ratherthan demolish.
Limitations
Absenceofa comprehensive heritagevalue assessment. Proposed framework risks recommending material changesthat mayreduce embodied energybut compromise theheritage building’s signiicance
Recommends developingamultidisciplinary procedurethat servesasevidence toattractthepolicy makerssothat considerationof embodiedcarbon becomes mandatoryin policyand legislation.
Asix-stageCircular Refurbishment Framework focusingon Mapping,Selective Disassembly, (Re)Design,(New) Products, (Re)Construction, Operation. Proposedtaxand permit-based
Thestudyfails toapplyits indingstorealworldheritage conservation projects. Without empirical testing,the proposed framework remains theoretical.
Whilethe frameworkis theoretically sound,ithasn’t yetbeen broadly implemented orvalidatedin real-world projects.
Casestudyis speciicto
incentivestructures linkedtoCE compliance. Emphasizedthe roleoflocal authoritiesin enablingCE through infrastructureand guidelines.
Portugal. Framework requires further exploration. CEassessments relyoncomplex BIMandLCA data,which maynotbe readily availableor standardized.
2021 FreyaWise,Derek Jones&Alice Moncaster(2021) Reducingcarbon fromheritage buildings:the importanceof residents’views, valuesand behaviours,Journal ofArchitectural Conservation,27:1-2, 117-146,
2021 HannahBaker,Alice Moncaster,Hilde Remøy&Sara Wilkinson(2021) Retentionnot demolition:how heritagethinkingcan informcarbon reduction,Journalof Architectural Conservation,27:3, 176-194,DOI: 10.1080/13556207. 2021.1948239
Exploratorysurvey LifeCycle Assessment(LCA)
2021 Fufa,S.M.;Flyen,C.; Flyen,A.-C.HowCan
Threedetailedcase studiesinaidof documentreviews, stakeholder’s, expert’sinterviews
The inalsurvey focusedonmany areaslikebuilding signiicance, heritagevalues, energybehaviours andsystems,indoor environmental quality.Mainly emphasisonvalues integratedwith sustainability.
Evenwhennot oficiallyprotected, buildingswerekept fortheir contributionto place-makingand identity.No equivalentpolicy enforcementexists forembodied carbonintheUKor Australia (Netherlandsis ahead).Toolslike BREEAMorLEED maymention embodiedcarbon butdon’tenforceit asadecidingfactor.
Smallersample sizehence. relativelyless statisticaldata toanalyse.Also speciictoone geological scope.
Thestudyis qualitative, basedon perceptions, interviews,and planning outcomes—not directcarbon calculations.
AppliedLCAusing varioustoolslike LCAnotyetwidely mandatedor Whileheritage importance
ExistingBuildings withHistoricValues Contributeto AchievingEmission Reduction
Ambitions?Appl.Sci. 2021,11,5978.
2019 FWiseetal(2019)
IOPConf.Ser.:Earth Environ.Sci.329 012002
Considering embodiedenergy andcarbonin heritagebuildings–areview
2019 Ding,Grace&Ying, Xiaoyu,(2019).
Embodiedand operatingenergy assessmentof existingbuildings–Demolishorrebuild Energy,Elsevier,vol. 182(C),pages623631.
SimaPro,OneClick LCA,ZEBTool.
2011 StephenPullen1and HelenBennetts2 (2011)Valuing embodiedenergyin theconservationof historicresidential buildings1University ofSouthAustralia, Adelaide,Australia 2Director,Helen BennettsSustainable Design,Adelaide, Australia
anarrative systematic literaturereviewof embodied energy/carbonin heritagebuildings
standardizedfor heritagebuildings. OnlyveryfewLCA studiesexistthat fullyintegrate cultural,social,and environmental values.
Exploresthe researchgaponthe needformore evidencetohelp buildthecaseto policymakersthat thecalculationof lifecyclecarbon shouldbeincluded inregulation.
CADsoftware entitledDesigner's SimulationToolkit (DeST)forthecase studybuildings, developedby TsinghuaUniversity usingthedefault settingsforvarious zoningandclimate datatoprovide comparativeresults forallbuildings assessed.
CostestimatesArchicentreCost Guide(AIA,2010) AccuRatesoftware
Incomparing resultsforboththe historicand modernbuildings, thelittledifference inboththe embodiedand operatingenergy hasprovideda strongargument forbuilding conservationrather thandemolition.
Indicatesbymeans ofacasestudythat thereare environmental advantages,andthe costsavingsalone maynotbe suficientto encourageowners toavoiddemolition andrebuilding.
inluenced decisions,it wasn'tincluded incarbon modelling.
Minimalfocus onoperational carbon-an incomplete viewoftotal lifecycle impacts.
Economicand socialfactors overlookedfocuses primarilyon technicaland environmental aspects.
Thestudydoes notfactorin theimpactof resident behaviouror heritagevalues ontheenergy performanceof conservation forhistoric residential buildings.
calculatorusedforthestudyofNUSArCLab,whichcanserveasamodelforfuture assessmentsofembodiedenergyinothershophousesoftheBlairPlainConservation Areaorglobally.Additionally,athoroughvalueassessmentoftheNUSArCLabwillbe conducted,includingitshistorical,collectivememory,andintangibleaspects, offeringinsightsintothelayersofhistoryembeddedintherootsofcolonialtimesof Singapore.Theresearchwillalsoprovideasustainabilityvalidation,employing mAAN’sButterlyMethodforamulti-dimensionalviewofthebuilding’s environmental,social,andeconomicsustainability.Basedonthese indings,the studywillofferpracticalpolicyrecommendationsforproposingamulti-disciplinary framework.
2. Understanding 141 Neil Road
2.1
SelectionCriteria
Theselectionofcasestudiesforthisresearchisguidedbytheirrelevanceto theintersectionofheritageconservationandenvironmentalsustainability, particularlywithinthecontextofurbandevelopmentandclimatechangediscourse. Eachcasemustinvolveaheritagebuildingorsitethatfacedpotentialdemolitionor extensiveredevelopment,whereenvironmentalconcernssuchasembodiedenergy, carbonfootprint,orlifecycleimpactscouldbecentraltotheconservationdebate. Emphasisisplacedoncasesthatgeneratedpublicorpolicy-leveldiscussion, includingcommunityengagement,orgovernmentorganisationsintervention,and eventhosethatattractmediaattentiontospreadawareness.Priorityisgivento examplesthatincorporateavailablequantitativeenvironmentaldatatosubstantiate
sustainabilityclaims,therebystrengtheningtheanalyticaldepthofthestudy.The selectedcasesshouldbesituatedinandaroundurbansettingstomaintain consistencywiththebroaderthemeofsustainableurbandevelopment. Furthermore,comparabilitytoSingapore’ssocio-politicalandclimaticcontextis consideredessential,enablingmoremeaningfulinsightsandapplicabilitytolocal conservationstrategies.Arangeofoutcomeswhethersuccessfulconservation, partialredevelopment,ordemolitionwillbeincludedtoprovideabalanced perspective.Lastly,casesmustbeaccessible,well-documentedthroughacademic publications,governmentreports,ormediasourcestoensuretheavailabilityof reliabledataforanalysis.
TheArchitecturalConservationLaboratory(ArCLab),partoftheDepartment ofArchitectureattheNationalUniversityofSingapore,isselectedasacasestudy duetoitsaccessibility,availabilityanddedicationinadvancingthedocumentation andconservationofhistoricfabricthroughinnovativetechniques,creativedesign, andpolicyresearch.6LocatedinaconservedbuildingatNeilRoad,ArCLabis equippedwithstate-of-the-arttools,including3Dscanners,drones,3Dprinters,and spectrophotometers,enablingcutting-edgecross-disciplinaryresearchand collaboration.NUSArCLabwasestablishedinJanuary2022withfourkeygoals:(i) augmentingtrainingcapabilitiesinbuiltheritageconservation;(ii)developing innovativeconservationtechnologies;(iii)conductinghigh-impactresearchon broaderconservationissuesand(iv)promotingclimateresilienceandnet-zero retrofitinhistoricbuildings.
6 https://news.nus.edu.sg/new-living-laboratory-to-advance-sustainable-heritage-management/
Afterbeinguninhabitedfordecades,thetownhousehascomealiveagainasa conservationclassroomandlaboratory7.NUSArCLab’sresearchersaretryingtofind waystomakeSingapore’sheritagebuildingsgreenamidclimatechange.A forthcomingconservationsensitiverepairofthepropertyisslatedtobecompleted in2027.Theresearchershopetheproperty’srefurbishmentwilluncoverwaysto makeheritagepropertiesmoreenvironmentallyfriendlyandshowthewayfor Singapore’sotherconservationbuildings.
2.2 StudyArea
Morethan6,500shophousesinSingaporehavebeenconservedfortheir historicalandculturalvalue.Theformalconservationofshophousesbeganinthe 1980s,withtheSingaporegovernmentrecognisingtheneedtopreservetheseiconic buildingsinspiteofrapidurbandevelopment.Thepreservationofshophouses becameanintegralpartofSingapore’surbanplanningstrategy,particularlywiththe establishmentofconservationdistrictssuchasChinatown,KampongGlam,and TiongBahruetc.Thesedistrictsweredesignatedfortheprotectionoftheirunique architecturalandhistoricalvalue,andshophouseswithintheseareaswerecarefully restoredandmaintainedtorelecttheiroriginalcharacter.
Whilenotallshophousesinthedesignatedareasareconserved,asigniicant numberofthemhavebeenrestoredandprotectedunderconservationguidelines, maintainingtheirhistoricalintegritywhilebeingadaptedformodernuse.The conservationprocessinvolvesnotonlytherestorationofthebuilding’sphysical featuresbutalsotheadaptationofthesestructuresforcontemporaryuses,suchas
7 Wei, X., Zhou, H., Joshi, N., & Tang, M. (2024). Beyond Preservation: Heritage as an Educational Practice Process at 141 Neil Road, Singapore. Buildings, 14(5), 1225. https://doi.org/10.3390/buildings14051225
Fig 3. Location map of 141 Neil Road in Blair Plain Conservation Area, Singapore (source: URA, 2019)
2.3 HistoricalBackground
Fig.4 Timeline of 141 Neil Road, Singapore (Source: Wei, X., Zhou, H., Joshi, N., & Tang, M. Beyond Preservation: Heritage as an Educational Practice Process at 141 Neil Road, Singapore. Buildings,2024)
Constructedalongoneoftheoldesttransportationroutesofcolonial Singapore,141NeilRoadispartofahistoricneighbourhoodsknownasoneofthe earliestlocalPeranakanenclaves.9
ThePortabellafamily,whohavebeeninvestinginSingaporepropertiessince 2008,donatedthetownhousetotheNationalUniversityofSingapore(NUS)inearly 2022foruseasatrainingcentreandarchitecturalconservationlaboratory,which NUShasnamedArClab.
Thefamilyalsodonated$2milliontowardsthebuilding’srepairand conservationworks.
9 “Peranakan tiles also known as majolica tiles are a vibrant testament to the community's rich cultural legacy. They were commonly used in Peranakan homes from the mid-1800s to 1950s to adorn the facades and interiors. Mostly imported from Europe and Japan, these tiles were favoured by the Peranakans in Singapore and Malaysia. These colourful tiles often feature intricate designs, including floral patterns, fruits, and animals, showcasing a blend of Art Noveau and Art Deco designs, and Chinese-inspired motifs.” https://nus.edu.sg/alumnet/thealumnus/story/people/spotlight/unveilingperanakan-heritage-a-journey-through-culture-sights-and-tradition
Fig.5 Photo taken from 141 Neil Road, Singapore in 1983 (Source: The Straits Times, 2024)
3. Methodology
Theresearchwillemployaquantitativemethodofapproachthatcombines archivaldatawithanalysistoscientiicallyestablishthemeritsofconservationover demolition.
3.1 QuantitativeResearch
3.1.1
CarbonCalculationsforheritagebuildings
Thissimplecarboncalculatorexaminesbothembodiedandoperational energytodeterminetheoverallenvironmentalimpactofeachapproach.10
CalculationofoperationalenergyandCO₂analysiswasdevelopedbyEnergyStudies Institute,NationalUniversityofSingapore(NUS),aspartofastudycommissionedby JurongTownCorporation(JTC)andincollaborationwithBuildingandConstruction Authority(BCA)andSingaporeGreenBuildingCouncil(SGBC).Thestudyanalysed annualenergyconsumptionbyprovidingvariousdataofthebuildinglike loorarea, materialsused,numberofstoreysetc.
Theuseofthissimplecarboncalculatorislimitedto(a)Calculatingthe carbonfootprintformaterialsusedlikewood,steel,concrete,glass(b)Considering theconstructionmethodsandenergyconsumptionduringthebuilding’screation. (c)Estimatingtheoperationalenergycostsoverthebuilding'sexpectedlifetime. Whilethelistedcriteriaoraspectsareessentialcomponentsoftheframework, additionalelementsmayalsobeconsidered.
10 https://www.sgbc.sg/embodied-carbon-calculator/
Thiscanbequantitativelyassessedthroughthewebgraph(ig.6),wherethe emotionalandrationaldimensionsaresymbolizedasthetwowingsofabutterly, representingthedualforcesthatshapetheexperienceandperceptionofheritage.12
Fig.6 mAAN’s Butter ly Method graph illustrating values in layers of time period (Source: Hermawan, B & Sholihah, Baiq. (2020). Cultural heritage as city identity case study of Ngawi, East Java, Indonesia. IOP Conference Series: Earth and Environmental Science. 447. 012040. 10.1088/1755-1315/447/1/012040.)
12 The butterfly diagram is a data collection technique that is based on someone's experience, taste and attachment to an object. This butterfly diagram comprises the values of memory, history, love, condition, happiness, and universality. The better the potential of the object will form a more perfect butterfly wing.
4. Findings and Discussion
4.1 QuantitativeFindings(EmbodiedEnergy&CarbonAnalysis)
AdetailedanalysisoftheNUSArCLab,incorporatingdatasuchastotal loor area,constructionmaterials,numberof loors,andotherrelevantparameters,was conductedusingacarboncalculator.Thisenabledthecalculationofseveralkey carbonmetrics,includingthetotalembodiedcarbonperunitarea,operational carbonperunitarea,andthetotalcumulativecarbonperunitareaovera50-year period.Theresultsindicatethatthetotalembodiedcarbonperunitareais400 kgCO2e/m²,whiletheoperationalcarbonperunitareais90.58kgCO2e/m².After50 years,thetotaloperationalcarbonperunitareaisprojectedtobe5.32kgCO2e/m².
Notably,thehighinitialembodiedcarbonrelativetotheenergyrequiredfor operationsuggeststhat,witheffectiveenergystorageandreuseoverthenext50 years,operationalenergydemandscouldbesigniicantlyreduced—from90.58 kgCO2e/m²to5.32kgCO2e/m².
Thegraph(Fig.7)visuallyreinforcesthisargumentbyclearlydemonstrating thelong-termbeneitsofconservingandupgradingtheNUSArCLab,asopposedto demolishingthebuilding.Demolishingtheexistingstructurewouldresultina considerablelossofembodiedenergyfromtheenergyalreadyinvestedinthe extraction,processing,constructing,transportation,andassemblyofbuilding materials.Incontrast,optingforminorrefurbishmentorretroittingrequires signiicantlylessoperationalenergy.
However,ifthebuildingisdemolishedinsteadofupgraded,thisdecision coulddiminishorinvalidateupto94%ofthepotentialreductionincarbon emissionsandcarbonfootprintthatwouldhavebeenachievedthroughenergy-
Existing Scenario of NUS ArCLab
EmbodiedCarbonperUnitArea
OperationalCarbonperUnitArea
TotalCumulativeCarbonperUnitAreaafter50years
TotalCumulativeEmissions-Existing (tonnesCO2e)
Fig.7 graph showing the amount of
assessmentsindicateaconvergenceofemotionalreverenceandintellectualrespect forthepast,wherepersonalmemoriesandcollectivehistoricalnarrativesare perceivedassigniicantandpositiveanchors.
Inthepresent,emotionalresponsesaredominatedbylove,whichagain reachesthemaximumrating,relectingthecentralityofaffectiverelationshipsin currentlivedexperience.Whilesomeviewthecurrentconditionverypositively, othersrateitpoorly,indicatingafragmentedandpossibleopportunityforrepairand maintenance.Thisdisparitybetweentheemotionalconstancyofloveandthe rationaluncertaintyofconditionhighlightsatensioncharacteristicofpresent-day life,whereemotionalbondspersistdespiteunstableorunequalexternalconditions.
Lookingtowardthefuture,emotionalprojectionsarestronglyoptimistic, withhappinessreceivingapeakrating.Thissuggeststhatindividualsassociatethe futurewithemotionalfulilmentandwell-being.
Anotablefeatureofthewebgraphisitsvisualsymmetry,particularlythe mirroredtrajectoriesbetweentheemotionalandrationaldomains.Overall,the diagramrevealsacognitive-affectivestructureinwhichthepastisidealized,the presentisemotionallysustainingbutrationallyinconsistent,andthefutureis viewedwithbothhopefulsentimentandintellectualconvictionbyanchoring identityinmemoryandprojectingvaluesintothefuture.
InapplyingmAAN’sButterlyMethodtoevaluatethesigniicanceoftheNUS ArCLablocatedat141NeilRoad,thefollowingcomponentsareassessed.
NUSArCLabwithitsarchitecturaltypology,constructiontechniques,and materialpaletteisanemblematicofSingapore’sbuiltheritagewhichoffersrich insightsintotheregion’scolonialpastandclimaticadaptations.Thisstructure servesasaspatialandmaterialarchiveofmemory,carryingemotionalassociations
ArCLabis,therefore,asitewherepastandpresentcoalesce-showcasingamodern academiclaboratoryhousedwithinabuildingofhistoricalsigniicance.
4.3 AssessmentofGreenMarkScheme
SomeCriteriaorAspectstoEvaluateGreenMarkScheme
TheGreenMarkSchemeisanassessmenttoolthatevaluatesheritage buildingslikeshophousesbasedontheirenvironmentalperformanceand sustainabledesign.Thepurposeofevaluatingthisschemeistomakeconservation approachandadaptivereuseasapreferablealternativetodemolitionandnew construction.Thiscomprehensiveframeworkaimstodeterminethebeneitsof GreenMarkcertiicationwhicharefurtherdiscussedindetail.Inadditiontothe latestcriteriadevelopedbytheBuildingandConstructionAuthority(BCA,2021)of Singapore,thisevaluatestherelationshipbetweenenvironmentalvalueandrangeof otherenvironmental,operational,andsocialfactorsthatcontributetotheoverall sustainability.
4.3.1Authenticity
Preservingauthenticitybyusingtraditionalmaterialsandrepairtechniques ofteninvolvessourcingorsalvagingoriginalorsimilarmaterials.Thisreducesthe needfornewmaterialproduction,therebyloweringembodiedenergy.Retaining originalelementsinsteadofreplacingthemconservestheenergyalreadyinvestedin theexistingfabricofthebuilding,whichiscentraltoheritagesustainability.
4.3.2Availability
Usinglocallysourcedmaterialsminimizestheembodiedenergyassociated withtransportation.Additionally,employingvernacularmaterialsandmethods incorporatedovergenerationstendstobelessenergy-intensivethanindustrialized constructionsystems.Thesepracticesreducetheneedforhigh-energyprocessing andpromotematerialeficiencytailoredtolocalclimates.
4.3.3HonestRepair
Minimalinterventionandreversibilitypreservemuchofthebuilding’s existingstructure,whichinitselfisaconservationofembodiedenergy.Byavoiding full-scalereplacementsandoptingfortargetedrepairs,thetotalenergyexpenditure remainslow.Futureinterventions,ifneeded,canbedonewithsimilarlow-impact strategies,maintainingaleanembodiedenergyproileovertime.
4.3.4
InnovativeApproach
Digitaltoolsandtechnologieslike3Dscanning,BuildingInformation
Modellingenablemorepreciseplanningandreducematerialwastebyimproving accuracyinrestorationwork.Althoughthetoolsthemselvesmayrequiresomeinitial energyinput,theyleadtoreducedembodiedenergyinthelongtermbypreventing overproductionandpromotingeficientresourceuse.
4.3.5
SustainabilityPractices
Embodiedenergyisdirectlyaffectedbythematerialsandsystemsintroduced duringinterventions.Reusingoriginalbuildingcomponentslikebricks,stones,and timbersigniicantlylowersembodiedenergycomparedtoproducingnewmaterials. Similarly,installingpassivedesignelementslikeimprovedventilation,daylighting
reducesfutureoperationalenergyneeds,complementingembodiedenergy conservationbyextendinglifecycleeficiency.
4.3.6
CircularEconomy
Theprincipleofreuseandrepurposingliesthemainfocusofreducing embodiedenergy.Salvagingandreintegratingmaterialsmeanstheinitialenergy investedinthosematerialsisextendedacrossmultiplelifecycles.Thissigniicantly lowersthedemandfornewresourceextractionandmanufacturing,keepingthetotal embodiedenergyfootprintminimal.
4.3.7
AdaptiveReuse
Adaptivereusepreservesthebuilding’scorestructure,meaningthe embodiedenergyoftheoriginalconstructionisnotwasted.Byavoidingdemolition andnewconstruction,theembodiedenergysavedissubstantial.Evenwhenminor alterationsareneeded,iftheyarereversibleandmaterial-conscious,thenetenergy impactremainslow.
4.3.8Legislation
Complyingwithcontemporarycodesfor iresafetyoruniversalaccessmay necessitateupgradesthatintroducenewmaterials.However,carefulselectionof energy-eficient,low-impactmaterialsthatarecompatiblewiththeoriginal structurecanmitigateadditionalembodiedenergy.Encouraginggreen-certiiedor recycledmaterialsthroughpolicycaninstitutionalizeembodiedenergyreduction.
4.3.9EducationandPromotion
Educationinluencesembodiedenergyindirectlybypromotingawareness andencouragingtheadoptionoflow-energy,sustainableconservationpractices. Whenstakeholdersunderstandtheenvironmentalimpactofmaterialchoicesand interventions,theyaremorelikelytooptforenergy-eficientsolutions.
4.3.10CommunityEngagement
Community-ledconservationoftenprioritizesmaintenanceandsmall-scale interventions,whichnaturallyreduceembodiedenergycomparedtomajor overhauls.Additionally,localengagementcansupportmaterialreuseinitiativesand trainingintraditional,low-energytechniques,furthercontributingtoenergyconsciouspreservationefforts.
S.NO CRITERIA FOR GREEN MARK IN HERITAGE BUILDINGS
1
1.1 Authenticbydesignlanguage
1.2 Authenticbymaterials
2
2.1 Craftsmanship/Technique
Section1-Authenticity
Energyalreadyembodiedinthestructure’s formandlayoutispreserved
Reducestheneedfornewmaterial production
Section2-Availability
Vernacularmethodstendstobeless energy-intensivethanindustrialized constructionsystemsandclimateoriented.
3
2.2 Locallysourcedcompatiblematerials
Minimizestheembodiedenergyassociated withtransportation
Section3–HonestRepair
3.1 Minimalinterventionmaximumretention
4
3.2 Reversibleandlegiblerepair
4.1 Useofsmarttechnology
Preservemuchoftheenergystoredin building’sexistingstructure
Allowingfutureinterventionstoupdatethe buildingwithoutfurthermateriallossor excessiveenergyconsumption.
Section4–InnovativeApproaches
4.2 Uniquesolutionstoenvironmental challenges
Promoteeficientresourceuse
Reduceembodiedenergyinthelongterm bypreventingoverproduction
5.5 FutureResearchScopeandConclusion
Despitethelimitations,thisdissertationopensseveralavenuesforfuture researchandpracticalapplications.Futureresearchcouldinvolveempiricalstudies withprimarydatacollectionfromheritagebuildingsinSingapore,suchasenergy audits,carbonfootprintanalysis,andresourceefficiencyevaluations.Thiswould offeramorecomprehensiveunderstandingoftheenvironmentalimpactsassociated withadaptivereuseversusdemolition,basedonmoreintenseperformancedata. WhilethedissertationfocusedonSingapore,futurestudiescouldexplorethe applicabilityofthefindingstoothercitiesglobally,especiallyinregionswithsimilar challengesofurbandevelopmentandheritageconservation.Comparativestudies couldrevealhowdifferentregulatoryframeworks,climateconditions,andeconomic landscapesaffecttheviabilityofadaptivereuseversusdemolition.Futurestudies couldinvestigatethelong-termenvironmentalandsocialimpactsofadaptivereuse projects.Thiscouldincludemonitoringenergyperformance,resourceconsumption, andcommunityengagementinheritagesitesafteradaptivereuse,providinga clearerpictureofthesustainabilitybenefitsovertime.Investigatingthepoliticaland socialdynamicssurroundingheritagepreservationcouldprovideinsightsintohow policieslikeGreenMarkcanbeimprovedtobettersupportheritageconservation efforts.
Inconclusion,whilethisdissertationcontributestotheexistingdiscourseon heritageconservationandsustainability,therearenumerousopportunitiesfor futureresearchtobuildonthesefindingsandtherebyrefinestrategiesfor integratingenvironmentalvaluesintoheritageconservationpractices.
5.6 SigniicanceoftheStudy
Theuniquecontributionofthisstudyliesinitscomprehensiveapproachto examiningtheintersectionofheritageconservationandsustainability,particularly withinthecontextofSingapore’srapidlyevolvingurbanlandscape.Thisresearch successfullybridgesthegapbetweenthe ieldsofenvironmentalscience, architecture,heritageconservation,andurbanplanning,offeringaholisticviewof thecomplexchallengesdecision-makersfacewhencontemplatingthefateof heritagestructuresinamoderncity.
Byevaluatingthecarbonfootprints,embodiedenergy,andresourceeficiency ofadaptivereuseversusdemolition,thisdissertationoffersaconcrete,data-driven analysisthatcandirectlyinformpolicydecisionsandurbandevelopmentstrategies. Thisapproachgoesbeyondqualitativeassessmentsofhistoricalorculturalvalue, addingalayerofenvironmentalaccuracytothedebateaboutheritageconservation. Itrepresentsaperspectiveinunderstandinghowadaptivereusecanbeaviable, sustainablealternativetodemolitionincitieswherespaceislimited,and environmentalconcernsarepressing.
Moreover,thisstudyisuniqueinitscriticalexaminationoftheexisting policies,particularlySingapore’sGreenMarkcertiication,andtheirapplicationto heritagebuildings.Whilepreviousstudieshaveaddressedgreenbuilding certiicationsorheritageconservationindependently,fewhaveexaminedhow existingsustainabilitypoliciesfailtoaccommodatetheuniquechallengesposedby heritagestructures.Thisgapinliteratureiscrucialbecauseitenablesamore nuancedunderstandingofhowpoliciesandstandardscanbeadaptedtobetter incorporateheritageconservationintosustainabledevelopmentframeworks.By proposingconcretepolicyadaptations,thisdissertationnotonlyhighlightsthe
6. Bibliography
Al-Zrigat, Z.M. (2025). BIM framework to minimize embodied energy in heritage buildings: old downtown Amman case studies. Facilities,43(1/2),149–171.
https://doi.org/10.1108/F-07-2024-0101
Baker, H., Moncaster, A., Remøy, H., & Wilkinson, S. (2021). Retention not demolition: how heritage thinking can inform carbon reduction Journal of Architectural Conservation,27(3),176–194.
https://doi.org/10.1080/13556207.2021.1948239
Building and Construction Authority (BCA).(n.d.). Green Mark Assessment Criteria and Policies.SingaporeGovernmentAgency.
Ding, G., & Ying, X. (2019). Embodied and operating energy assessment of existing buildings – Demolish or rebuild. Energy,182(C),623–631.
Fufa, S.M., Flyen, C., & Flyen, A.-C. (2021). How Can Existing Buildings with Historic Values Contribute to Achieving Emission Reduction Ambitions? Applied Sciences, 11(5978).https://doi.org/10.3390/app11135978
Fernandes, J., & Ferrão, P. (2023). A New Framework for Circular Refurbishment of Buildings to Operationalize Circular Economy Policies Environments,10(51).
https://doi.org/10.3390/environments10050051
Hermawan,B&Sholihah,Baiq.(2020).Culturalheritageascityidentitycasestudy ofNgawi,EastJava,Indonesia.IOPConferenceSeries:EarthandEnvironmental Science.447.012040.10.1088/1755-1315/447/1/012040.
Historic England. (n.d.). Sustainable Management of Historic Buildings
https://historicengland.org.uk
ICOMOS. (1964). International Charter for the Conservation and Restoration of Monuments and Sites (The Venice Charter)
https://www.icomos.org/charters/venice_e.pdf
ICOMOS. (1994). The Nara Document on Authenticity. https://www.icomos.org/en/179-articles-en-francais/ressources/charters-andstandards/386-the-nara-document-on-authenticity-1994
Jackson, M. (2005). Embodied Energy and Historic Preservation: A Needed Reassessment. APT Bulletin: Journal of Preservation Technology,36(4),47–52.
Mahmad, M.S., et al. (2024). Considering embodied carbon assessment into conservation decision-making IOP Conference Series: Earth and Environmental Science,1347,012024.
Pullen, S., & Bennetts, H. (2011). Valuing embodied energy in the conservation of historic residential buildings.UniversityofSouthAustralia,Adelaide.
Rajah, Indranee. Speech at the International Green Building Conference 2023. MinistryofNationalDevelopment,Singapore.2023.
Quotedin:TheStraitsTimes,2024.
Singapore Green Building Council (SGBC). (n.d.). Building Embodied Carbon Calculator (BECC) https://www.sgbc.sg/embodied-carbon-calculator/
7. Appendices
Semi-structuredinterviewquestionsandprompts
Appendix1.CarbonCalculator–DataCollection&AssessmentPrompts
Objective:Togatherdetailedquantitativeandqualitativedatarelatedtothe embodiedandoperationalcarbonofNUSArClab,enablingalifecyclecarbon assessment.
BuildingInformation&TechnicalSpeciications
1. Whatisthetotal loorareaandnumberof loorsofthebuilding(inm²)?
2. Whataretheprimaryconstructionmaterialsused(walls,structure,roof, inishes)?
3. Hasthebuildingundergoneanypreviousretroittingormaterial replacement?
EmbodiedCarbonInputs
4. Canyouprovideabillofquantitiesormaterialspeciicationsforthe structure?
5. Wereanylow-carbonorrecycledmaterialsusedinpastinterventions?
6. Istheredataavailablefrommaterialsuppliersorcontractorsregarding embodiedemissions?
OperationalCarbonInputs
7. Whatisthecurrentannualenergyconsumption(inkWh)?
8. Whataretheprimaryenergysources(electricity,gas,renewables)?
9. Arethereanyactiveorpassivedesignstrategiesimplementedtoreduce energyuse?
10.Haverenewablesystems(e.g.,solarpanels,naturalventilation)been installed?
Lifecycle&Performance
11.Whatistheprojectedlifespanofthebuildingunderitscurrentuse?
12.Howfrequentlyisenergyusereviewedoroptimized?
13.Haveanygreenmarkupgradesorincentivesbeenproposedor implemented?
Appendix2.mAAN’sButterlyMethod–HeritageSigniicanceEvaluationPrompts
Objective:Toassesstheemotional(intangible)andrational(tangible)signiicanceof theNUSArClabwithinitscommunityandarchitecturalcontext,acrosspast,present, andfuturedimensions.
Past(Historical&EmotionalSigniicance)
1. Whathistoricaleventsorculturalnarrativesareassociatedwiththebuilding?
2. Whatroledidthebuildingplayinthecommunity’spast?
3. Arethereanylocalmemories,stories,ortraditionstiedtothebuilding?
4. Howdoyouperceivetheemotionalconnectionbetweenthecommunityand thisstructure?
Present(CurrentUse&CommunityInteraction)
5. Whatisthecurrentfunctionofthebuilding,andhoweffectivelydoesitserve thatpurpose?
6. Howaccessibleandinclusiveisthespacefordifferentusergroups?
7. Inwhatwaysdoesthecurrentuserelectorconlictwiththebuilding’s heritageidentity?
